The art of hoop rolling for sport, amusement, exercise or other purpose is of old and uncertain origin as alluded to in U.S. Pat. No. 3,827,180 to Phillips, several of the myriad of other patents which have issued thereon being cited therein as exemplary of the art to which the present invention pertains.
Propelling trundles are of two general types, one being that in which the hoop is not captured, as exemplified by the U.S. Pat. to Rendon, No. 2,984,937, and the other that in which the hoop is captured, as exemplified by the Phillips patent above, U.S. Pat. No. 1,356,023 to Cyr and U.S. Pat. No. 2,970,403 to Land. While the capturing type has advantages when used with a truly circular hoop which normally may roll at uniform velocity, it becomes of further advantage when used with a non-circular hoop which rolls at non-uniform velocity as set forth in U.S. Pat. No. 3,935,668 to Phillips.
The art also reveals that a hoop may be a continuous ring without ends (U.S. Pat. No. 3,827,180) or formed in segments (U.S. Pat. No. 3,935,668). In the former, the trundle loop must be constructed in some manner to provide an opening therein to attach same to the hoop. In the latter, the hoop may be opened at a joint therein and an endless propelling ring threaded onto an end thereof. Thus, the use of a circular endless capturing ring would be feasible for use with this patent by disjointing one of the segments which, as will be apparent, is cumbersome. It logically follows that the ideal manner of attaching the trundle loop to the hoop resides in the loop construction, whether or not the hoop is endless. The prior art, of course, discloses various trundle loops which serve such purpose.